Properties of milk fat of crossbred goats

Abstract

An investigation was carried out to determine some of the physical and chemical properties of the milk fat of crossbred goats viz. Alpine x Malabari and Saanen x Malabari. A total of 183 milk samples were collected from six each of the two different crossbred goats and out of this 65 samples were used for determination of the size of the milk fat globules. The various fat constants were determined by analyse of ghee prepared by direct heating of cream separated out from the collected milk samples.

The average size of the milk fat globule of Alpine x Malabari and Saanen x Malabari was 2.556+ 0.110 and 2.702 + 0.038 microns respectively. The average value obtained for the melting point of Alpine and Saanen crossbred goats’ milk fat was 31.07 + 0.160 C and 31.36 + 0.130 C respectively.

The Alpine crossbred goats’ milk fat gave a refractive index of 1.4568 + 0.0001 and an iodine number of 24.95 + 0.28, whereas the corresponding values obtained for the milk fat of Saanen x Malabari goats were 1.4569 + 0.0001 and 25.09 + 0.35.

The Reichert-Meisal(RM) number and polensite value obtained for the milk fat or Alpine x Malabari goats were 28.14 + 0.18 and 3.52 + 0.15 respectively. The corresponding values for the Saanen crossbred goats’ milk fat were 28.61 + 0.15 and 3.64 + 0.12 respectively. The Alpine x Malabari and Saanen x Malabari goat milk fat gave an average saponification value of 235.1 + 0.7 and 234.6 + 1.1 respectively.

On statistical analysis of the data it has been found that there was no significant difference between the size of the fat soluble and the various other physical and chemical constituents of milk fat of the two groups of crossbred goats.

Towards the end of the lactation highly significant increased was noticed in the melting point, refractive index, iodine number, Reichert-Meisal number and polensite value and decrease in the size of the milk fat globule and saponification value of the milk fat of both the Alpine x Malabari and Saanen x Malabari goats.